1. Field of the Invention
This invention relates to a magnetic recording and reproducing device such as a so-called 8-mm video tape recorder.
2. Background of the Invention ln 8-mm video tape recorders which have been standardized recently and are commercially available, a magnetic tape is wound on a rotary drum through 221.degree.. Each of several sloped tracks is divided into a video signal recording region corresponding to a winding angle of 180.degree. (one field) and a PCM audio signal recording region corresponding to a winding angle of 36.degree.. As a result, both video signals and PCM audio signals can be recorded and reproduced. Furthermore, the video signal recording region is divided into five tracks each corresponding to a winding angle of 36.degree. so that six tracks in total are used for recording and reproducing PCM audio signals. In this case, the relation in phase between a head switching pulse (HSWP) for switching a pair of rotary heads A and B which are diametrically opposite to each other and different in azimuth from each other and the tracks (Trk1 through Trk6) is as shown in FIG. 8.
Similarly as in an ordinary 1/2-inch video tape recorder, the conventional 8-mm video tape recorder is used to record and reproduce both video signals and audio signals. Therefore, it is designed with preference given to recording video signals. Therefore, in many of the conventional 8-mm video tape recorders, the recording rotary head is used also as the reproducing rotary head. Also, therefore, a PCM audio signal cannot be after-recorded in synchronization with the PCM audio signal recorded in a predetermined track.
In some of the conventional 8-mm video tape recorders, the recording rotary head and the reproducing rotary head are separately provided. However, they are so arranged that the recording rotary head precedes the reproducing rotary head, for emphasizing the monitoring function. Although they are intended to permit an after-recording operation, the amount of precedence of the reproducing rotary head with respect to the recording rotary head is insufficient because they handle video signals. Thus, in the multiple tracks of the 8-mm video tape recorder, a PCM audio signal cannot be recorded in synchronization with the PCM audio signal recorded in a desired one of the tracks.